Embryonic Development

Question 1

Organogenesis

Answer 1

this is the formation of organ systems

- all organ systems exist in their primordial form by the end of week 4

Question 2

Morphogenesis

Answer 2

• this is the process of developing shape in the embryonic period
• two types: cephalocaudal folding and transverse folding

Question 3

Cephalocaudal folding

Answer 3

• this is the head and tail folding
• the head region grows the fastest due to the rapid development of the brain
  this is creating the future head and tail regions

Question 4

Transverse folding

Answer 4

this creates the future torso

Question 5

Teratogens

Answer 5

these are environmental agents that can disrupt development and cause congenital abnormalities

ex. drugs, alcohol, radiation, zika virus, some medications
- week 3-8 are particularly vulnerable

Question 6

Fetal period

Answer 6

• this is week 9 until birth

- this is marked by growth and maturation

Question 7

Critical periods

Answer 7

these are times when when systems or body parts are growing and they are the most vulnerable to beign affected by teratogens

Question 8

Windows of vulnerability

Answer 8

this is where something can effect something very major at a specific time but at a different time that same action would not cause the same major effect

-an example: when a specific part of the brain or organ is developing and it is at higher risk for things, like if you are abused from age 9-10 will have a smaller cerebral cortex because that is what is being developed but if you are abused from the age 11-13 you will have a smaller hippocampal volume

Question 9

when does the placenta begin to develop

Answer 9

week 2

- this is important because it is when the nutrients will begin to reach the embryo which allows for growth

Question 10

when is something considered a preterm birth

Answer 10

anything before 37 weeks

Question 11

embryonic development

Answer 11

this is fertilization through week 8

Question 12

what is important about folic acid

Answer 12

it is necessary for nervous system development

-thats why women of child bearing years take folic acid supplements

Question 13

what are the three germ layers

Answer 13

• these are three layers (ectoderm, the mesoderm and the endoderm) that all structures in the body will be produced from
• *don’t need to know names of layers

Question 14

what is the one system that doesn’t really age poorly

Answer 14

the endocrine organs operate effectively until old age

-only growth hormone and reproductive hormones change